Device for the elimination of piston flutter



Dec. 8, 1936. D. J. WHERRY DEVICE FOR THE ELIMINATION OF PISTON FLUTTER Filed July 2, 1936 INYENTOR. DHLE: Ll. WHERRY- Patented Dec. 8, 1936 I UNITED STATES DEVICE FOR THE ELIMINATION OF PISTON FLUTTER Dale J. Wherry, Des Moines, Iowa Application July 2, 1936, Serial No. 88,567

5 Claims.

The principal object of my invention is to provide a device that may be installed in the piston of an internal combustion motor that will automatically yieldingly control the lateral movement of the piston within the cylindcr thereby compensating for the wear of the moving parts as well as the expansion of the metal in the piston and cylinder walls of the engine.

A further object of my invention is to provide a device for installation in the pistons of an internal combustion motor that will not become caked with carbon or stick and which will always be held yieldingly against the cylinder wall .to prevent the flutter of the piston within the cylinder.

A still further object of this invention is to provide a device which will prevent the piston from rocking within the cylinder regardless of the speed of reciprocation of the piston within the cylinder, and at the same time will not interfere with the efficient distribution of oil to the friction surface of the piston, cylinder wall, and piston ring.

Still further objects of my invention are to provide a device for the elimination of piston flutter and vibration that: has great wearing qualities, is self-centering, will not wobble or twist, is non-abrasive in its action, and which may be readily and easily installed in the pistons of an internal combustion motor for aligning the piston within the cylinder in which the piston is operating even after the motor has experienced a great amount of usage.

A still further object of my invention is to provide a. device for the elimination of piston flutter that is extremely economical in manufacture and durable in use. I

These and other objects will be apparent to those skilled in the art.

My invention consists in the construction, arrangement and combination of the various parts of the device, whereby the objects contemplated are attained as hereinafter more fully set forth, pointed out in my claims and illustrated in the accompanying drawing, in which:

Fig. 1 is a cross-sectional view of a portion of the cylinder of an internal combustion motor, a piston, and my device installed ready for use.

Fig. 2 is a top cross-sectional view of a portion of the piston and cylinder wall taken on the line 22 of Fig. 1.

Fig. 3 is anenlarged bottom-sectional view of my device installed in a piston and taken-approximately on the line 3-3 of Fig.. 1. I

Fig. 4 is an enlarged side view of one of the forks with the flat spring and centering cone thereon before the device is installed in the piston.

Fig. 5 is an enlarged plan view of the spring retaining fork member.

There have been numerous attempts to create an economically manufactured device to be installed in the piston of an internal combustion motor to prevent piston flutter to compensate for the expansion and contraction of the metals used in the manufacture of piston and cylinder walls and to take up the play occasioned by the wearing of the cylinder wall surfaces. Piston expanders have been tried which merely expanded the the services of an expert in this line, develops considerable side play, and, due to the action of the heat within the motor upon the cup member, the operation of the device is at best uncertain, also the cups will sometimes become disengaged from the piston. The devices on the market are not applicable of all types and phases of pistons and are extremely abrasive in their action on the cylinder wall. I have overcome such disadvantages as will be apparent and as hereinafter set forth.

Referring to the drawing, I have used the numeral In to designate the ordinary cylinder of an internal combustion engine or like having therein the usual reciprocating piston I I. It is to such a piston that I install my device and which I will now, describe.

The numeral l2 designates a cylinder contact head or plug slidably mounted in a hole 'cut in the side of the piston approximatelyequidistant between the upper and lower end of the piston II. The outside of this head I2 is designed to frictionally engage the inside wall of the cylinder III as shown in the drawing. The numeral l3 designates a holding band about the inside peripheral edge of the head for the purpose of preventing the head 12 from splitting or-expanding. I have found, after a great amount of experimentation and practical use, that this head, to be efiicient in construction, non-abrasive, and long-wearing,

shouldbe constructed of an oil-impregnated wood,

pre-shrunk and obviously not as sensitive to temperature changes as would be a metallicone. I.

have used the numeral lLtodesignate a conehead l2. FI'henumeral l.i-designates a forked member positioned belowand'in longitudinal line 1 with thecenter of thehead I2. ,'I his ;forkedmember l5v is substantiallyflat,rests,transversely to the longitudinal axis of the piston and is.

one of its end portions formed into a sleeve. The numeral I'I designates a. pin rivet extending through the arms of the fork l5 and through the inside passageway of the sleeve formed on the end of the spring l6. Thus the fiat spring is pivotally mounted to the fork member IS. The numeral l8 designates a centering cone rigidly secured to the spring l6 and designed to operatively engage the conical recess 14 cut in the rear face of the head l2. The numeral l9 designates a similar forked member designed to be rigidly secured to the piston wall transversely to the pistons longitudinal axis and above the diametrical center of the plug l2. This fork member has a pin rivet 20 or the like through its arms for retaining the other end of the spring It as shown in Fig. 5 of the drawing.

' By the above construction and by reference to Fig. l of the drawing, it is readily apparent that my device is easily installed in the pistons of an internal combustion motor. A hole is drilled in the wall of the piston midway between its ends to receive the head l2. This hole is of slightly larger diameter than the diameter of the head I2. In longitudinal alignment with the center of the hole and spaced the required distance, two holes are drilled in the piston wall, one above and one below the hole cut for the head l2. These two holes are countersunk and are for the purpose of receiving the integrally formed rivets n the members I and I9 respectively. The member IS! with the pin rivet 20 in place is riveted in the upper hole cut in the piston. The head I2 is then placed in the large hole cut to receive it. The loose end of the spring I6 is then introduced between the arms of the member i9, under the pin 20, and the member l5 secured to the piston. The cone l8 will fit into the recess M in the back of the head [2.

When the piston is placed within the cylinder the head I2 is pushed against the tension of the spring l6 which continuously holds the face of the head I 2 in constant yielding contact with the cylinder wall.

By pivoting the spring IS on the member l5, and by allowing the other end of the spring to be confined between the rivet 20 and member IS, the spring I6 is confined at both ends, held in positive alignment and applies more pressure against the head l2 than would be the case if the spring l6 was secured merely at one of its end portions. Also by having the centering cone of a larger top diameter than the top diameter of the recess l4, any wear occuring between the cone l8 and recess ll of the head I2 will be compensated for, as the centering cone will merely sink deeper into the recess. Thus the head l2 will always be held in positive alignment within the hole cut in the piston wall and will obviously be free from any side play or twist and will be held against the cylinder wall at all times without binding on, the piston.

Thus it will be seen that I have provided a device for the elimination of piston flutter that may be easily installed in a piston, which remains in constant contact with the cylinder wall regardless of the speed of reciprocation of the piston or the worn shape of the cylinder. Furthermore, my device keeps the piston in constant alignment within the cylinder, has no cups or other container to become filled with carbon and sludge and to interfere with the free reciprocation of the head, and is non-abrasive in its action. My device is not apt to become disengaged from the piston and will allow the oil in the motor to perform its function without interference from my device. .Also my device is noiseless in operation and responsive to changing contour within the cylinder.

Some changes may be made in the construction and arrangement of my improved device for the elimination of piston flutter without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims any modified forms of structure or use of mechanical equivalents which may be reasonably included within their scope.

I claim:

1. In a piston, a head member designed to be slidably mounted in the wall of a piston, a forked member designed to be secured to the inner side of said piston, an elongated fiat spring having one of its ends pivotally mounted on said fork member and extending over one end of said head yieldingly holding said head in an outward position, and a second forked member retaining the other end of said spring on the diametrically opposite side of said plug.

2. In combination with a piston, a round head member slidably mounted in the wall of said piston transversely to its longitudinal axis and equidistant between its ends, a fork member secured to said piston and positioned to one side of said head member, a second fork member secured to said piston on the other side of said head member and in line with said head member and said first mentioned fork member, a recess in the rear face of said head member, an elongated spring operatively secured between said fork members and across the rear surface of said head member, and a lug rigidly secured to said spring engaging said recess; said spring forcing the face of said head outwardly beyond the pe-' riphery of said piston.

3. In a piston, a head member slidably mounted in the sidewall of said piston and extending beyond the periphery of said piston, an elongated spring secured to said piston on its inner side and extending over the rear center of said head, and a cone shaped centering element secured to said spring engaging said head.

4. In a reciprocating piston, a pre-shrunk oil impregnated wooden head member slidably mounted in the wall of said piston transversely to the reciprocating movement of said piston and extending beyond the peripheral edge of said piston, a curved face on one end of said head member for engaging the wall of a cylinder, a tapered recess in the rearward end of said head member, an elongated spring secured to said piston, and a tapered element secured to said spring yieldingly engaging said tapered recess in said head forcing said face of said head yieldingly outwardly.

5. In a reciprocating piston, a head slidably mounted in the wall of said piston and extending beyond the wall on each side, an elongated resilient member extending across the back of said head and secured to said piston, and a means secured to said resilient member yieldingly engaging the inner end of said head holding said head in alignment. 

